Projectile with enhanced rotational and expansion characteristics

ABSTRACT

A firearm projectile includes a plurality of holes spaced equidistant from each other, where each hole extends from an upper part to a lower part of the firearm projectile, and where each hole extends at an acute angle from a y-axis longitudinal centerline of the firearm projectile, in both z and x axes directions, causing an accelerated rotation of the firearm projectile upon firing and an expansion of the firearm projectile upon impact that causes sections of the firearm projectile to separate.

FIELD

The disclosed exemplary embodiments are directed to ammunition, and inparticular to a bullet or other projectile with holes or passages thatenhance performance.

BACKGROUND

FIG. 1 illustrates typical features of a bullet or projectile 100 thatmay be fired from a weapon. The projectile 100 may include an upper partincluding a meplat 105, referring to the tip of the projectile, and anogive nose 110, referring to the curved surface or ogival arch formingthe nose of the projectile. The projectile may have a secant ogive nosewith a cylindrical surface of the bullet or projectile secant to thecurve of the meplat, or a tangent ogive nose with a cylindrical surfacetangent to the curve of the meplat. The projectile may further include alower part including an ogive base 115 that provides a transition fromthe ogive nose to a cylindrical shank 120, a conical ramp 125 thatprovides a transition from the shank 120 to a bearing surface 130 whichengages a barrel of the weapon during firing, and a boat tail 135 thatoperates to reduce drag during flight.

The weapon generally includes a rifled barrel with internal helicalgrooves that cause a projectile to rotate around its longitudinal axiswhich somewhat improves stability during flight and may extend flighttime. However, the rifling profile is fixed and may not cancel theeffects of asymmetry of all projectiles used in the weapon and may notextend flight time significantly for all projectiles. Furthermore, theprojectile may be designed to expand upon impact, but is generallydesigned to deform without crumbling or separating.

SUMMARY

The present disclosure seeks to provide a projectile that is designed torotate around its longitudinal axis at an increased rate that impartsincreased stability, minimizes ballistic drop, and increases the time offlight, and is also designed to divide into sections that spread apartand separate from the projectile upon impact, causing a loss of mass andmomentum of the projectile within a target, making it more likely thatthe projectile and separated sections remain within the target.

In at least one aspect, the disclosed embodiments are directed to afirearm projectile having a plurality of holes spaced equidistant fromeach other, where each hole extends from an upper part to a lower partof the firearm projectile, and where each hole extends at an acute anglefrom a z-axis longitudinal centerline of the firearm projectile, in bothx and y axes directions, causing an accelerated rotation of the firearmprojectile upon firing and an expansion of the firearm projectile uponimpact that causes sections of the firearm projectile to separate.

The plurality of holes may be cylindrical.

The plurality of holes may be through holes.

Each hole may extend from an ogive nose to an ogive base of the firearmprojectile.

Each hole may extend from an ogive nose to a bearing surface of thefirearm projectile.

Each hole extends from an ogive nose to a shank of the firearmprojectile.

Each hole may extend from a meplat to a shank of the firearm projectile.

Each hole may extend from a meplat to an ogive base of the firearmprojectile.

Each hole may extend from a meplat to a bearing surface of the firearmprojectile.

The plurality of holes may be open at the upper part of the firearmprojectile and blind at the lower part of the firearm projectile.

The firearm projectile may be a pre-existing bullet through which theplurality of holes are machined.

The disclosed embodiments may include a method of manufacturing thefirearm projectile including placing an electrode proximate the upperpart of the firearm projectile, directing a stream of dielectric fluidtoward a space between the electrode and the upper part of the firearmprojectile, periodically applying an electrical potential between theelectrode and the firearm projectile causing a cyclical arcing betweenthe electrode and the upper part of the firearm projectile, causing anerosion of a portion of the upper part of the firearm projectile,resulting in individual ones of the plurality of holes.

The electrode may include a composition that may include one or more ofbrass, copper, copper graphite, graphite, tungsten, or any conductivematerial.

The dielectric fluid may include deionized water.

Periodically applying an electrical potential between the electrode andthe firearm projectile may include applying the electrical potential atbetween 50-250 volts DC or AC, and between 200 to 500,000 cycles persecond.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the various components of a typical bullet or projectile;

FIGS. 2A-2D illustrate an example of a projectile according to thedisclosed embodiments with through holes extending from an ogive nose ofthe projectile to an ogive base of the projectile;

FIGS. 3A-3D illustrate an example of a projectile according to thedisclosed embodiments with through holes extending from an ogive nose ofthe projectile to a bearing surface of the projectile;

FIGS. 4A-4E illustrate an example of a projectile according to thedisclosed embodiments with through holes extending from a meplat of theprojectile to a shank of the projectile;

FIGS. 5A-5D illustrate an example of a projectile with blind holes orpassages extending from a meplat of the projectile toward a bearingsurface of the projectile;

FIGS. 5E, 5F, and 5G depict section, side, and top views, respectivelyof the projectile of FIGS. 5A-5D;

FIG. 6 illustrates another example of a projectile with blind holes orpassages;

FIG. 7 illustrates an EDM process for fabricating through holes in aprojectile;

FIGS. 8A-8C show examples of the projectiles of FIGS. 2-4, respectively,fabricated using the EDM process and with electrodes in the throughholes illustrating the orientation of the through holes afterfabrication;

FIG. 9 illustrates an EDM process for fabricating blind holes in aprojectile; and

FIG. 10 shows an example of the projectile of FIG. 5A fabricated usingthe EDM process and with electrodes in the blind holes illustrating theorientation of the blind holes after fabrication.

DETAILED DESCRIPTION

The aspects and advantages of the exemplary embodiments will becomeapparent from the following detailed description considered inconjunction with the accompanying drawings. It is to be understood,however, that the drawings are designed solely for purposes ofillustration and not as a definition of the limits of the invention, forwhich reference should be made to the appended claims. Additionalaspects and advantages of the invention will be set forth in thedescription that follows, and in part will be obvious from thedescription, or may be learned by practice of the invention. Moreover,the aspects and advantages of the invention may be realized and obtainedby means of the instrumentalities and combinations particularly pointedout in the appended claims.

For purposes of the present disclosure, a round or cartridge may referto an assembly including a bullet, a case or shell with a propellant,and a primer. A projectile may refer to the bullet portion of a round orcartridge. A projectile may further refer to any object fired from aweapon.

A projectile and a method of fabricating a firearm projectile aredisclosed with holes or passages that cause one or more of anaccelerated rotation resulting in at least an approximate 10% increasein range or an expansion of the firearm projectile upon impact thatcauses sections of the projectile to separate. The accelerated rotationmay act to stabilize the projectile during flight, may operate to canceleffects of any asymmetry of the projectile, and may act to minimizeballistic drop, thus increasing the time of flight. The expansion of thefirearm projectile upon impact that causes sections of the projectile toseparate may cause a loss of mass and momentum of the projectile, makingit more likely that the projectile and separated sections remain withinthe target.

The plurality of holes may be spaced equidistant from each other, whereeach hole extends from an upper part to a lower part of the firearmprojectile, and where each hole extends at an acute angle from a y-axislongitudinal centerline of the firearm projectile, in both z and x axesdirections, causing the accelerated rotation of the firearm projectileand the expansion of the firearm projectile upon impact.

FIGS. 2A-2D illustrate different views of an exemplary projectile 200,referred to as a T9 projectile, with through holes 205 that may causeaccelerated rotation of the projectile 200 during flight. As shown inFIG. 2A, the through holes 205 may extend from an ogive nose 210 of theprojectile 200 to an ogive base 215 of the projectile 200. The throughholes 205 are generally cylindrical and straight, and may extend at anacute angle from a Z-axis longitudinal centerline, in both X and Y axesdirections. For example, as shown in FIG. 2B, the through holes 205 mayextend 40° from an ogive surface 220 of the ogive nose 205 of theprojectile 200 with adjacent through holes in the ogive baserotationally offset 60° from each other, as shown in FIG. 2C. FIG. 2Dillustrates a perspective view of the T9 projectile where an upper end225 of the through holes 205 may be offset approximately 0.07 inchesfrom the Z-axis longitudinal centerline. It should be understood thatthe number of through holes 205 is not limiting and any number ofsuitable through holes may be utilized. It should also be understoodthat the angles at which the through holes extend may be any anglessuitable for imparting an accelerated rotation to the projectile 200.

FIGS. 3A-3D illustrate different views of a projectile 300, referred toas a T11 projectile, that may have an accelerated rotation during flightdue to through holes 305. As shown in FIG. 3A, the through holes 305 mayextend from an ogive nose 310 of the projectile 300 to a bearing surface315 of the projectile 300. The through holes 305 may generally becylindrical and straight, and may extend at an acute angle from a Z-axislongitudinal centerline, in both X and Y axes directions. For example,as shown in FIG. 3B, the through holes 305 in the ogive nose 310 mayextend 10° from a Z-axis longitudinal centerline to the bearing surface315 where adjacent through holes in the bearing surface are rotationallyoffset 60° from each other, as shown in FIG. 3C. FIG. 3D illustrates aperspective view of the T11 projectile where an upper end 325 of thethrough holes 305 may be offset approximately 0.075 inches from theZ-axis longitudinal centerline. It should be understood that the numberof through holes 305 is not limiting and any number of suitable throughholes may be utilized. It should also be understood that the angles atwhich the through holes extend may be any angles suitable for impartingan accelerated rotation to the projectile 300. It should further beunderstood that depending on a distance the projectile extends along theZ-axis longitudinal centerline, the through holes 305 may extend fromthe ogive nose 310 of the projectile 300 to a shank 330 of theprojectile 300.

FIGS. 4A-4E illustrate an example of a projectile 400, referred to as aT10 projectile, with through passages, also referred to as through holes405, that may operate to cause the projectile 400 to expand upon impact.As shown in FIG. 4A, the through holes 405 may extend from a meplat 410of the projectile 400 to a shank 415 of the projectile 400. The throughholes 405 may generally be cylindrical and straight, and may extend atan acute angle radially from a Z-axis longitudinal centerline to theshank 415 of the projectile 400. As shown in FIG. 4B, the through holes405 may extend at a 10° angle radially from the Z-axis longitudinalcenterline, where adjacent through holes are rotationally offset fromeach other by 60° as shown in FIG. 4C. FIG. 4D shows a perspective viewof the T10 projectile, and FIG. 4E shows an exemplary point of entry formachining the holes offset approximately 0.023 inches from an outsideedge 430 of the meplat 10. It should be understood that the throughholes may extend at any angle suitable for extending radially from themeplat 410 to the shank 415 of the projectile 400. Furthermore, whilesix through holes 405 are depicted, it should be understood that anynumber of through holes may be utilized. Still further, it should beunderstood that the through holes 205 may also extend from the meplat410 to any one of an ogive base 420 or a bearing surface 425 of theprojectile 200.

FIG. 5A illustrates an example of a projectile 500, referred to as a T12projectile, with blind holes or passages 505 that may extend from ameplat 510 of the projectile 500 to toward a bearing surface 515 of theprojectile 500, but do not extend or penetrate through the bearingsurface 515. The blind holes 505 may operate to cause the projectile 500to expand upon impact. The blind holes 505 are generally cylindrical andstraight, and may extend at an acute angle radially from a Z-axislongitudinal centerline toward the bearing surface 515. The introductionof the blind holes generally results in a hollow cavity 520 within anogive nose 525 of the projectile 500, and a solid cone 530 within anogive base 530 of the projectile 500. In some embodiments, the blindholes 505 may be tapered. As shown in FIG. 5B, the blind holes 505 mayextend at a 6° angle radially from the Z-axis longitudinal centerline,where adjacent through holes are rotationally offset from each other by60° as shown in FIG. 5C. FIG. 5D shows a perspective view of the T12projectile. It should be understood that the blind holes 505 may extendat any angle suitable for extending radially from the meplat 510 to thebearing surface 515 of the projectile 500. Furthermore, while six blindholes 505 are depicted, it should be understood that any number of blindholes may be utilized. Still further, it should be understood that theblind holes 505 may also extend from the meplat 510 to any one of theogive base 530 or a shank 535 of the projectile 500.

FIGS. 5B, 5C, and 5D depict section, side, and top views, respectivelyof the projectile of FIG. 5A.

FIG. 6 illustrates another example of a projectile 600, referred to as aT12A projectile with blind holes or passages 505 that may extend from ameplat 610 of the projectile 600 to toward a bearing surface 615 of theprojectile 600, but do not extend or penetrate through the bearingsurface 615. The blind holes 605 are generally cylindrical and straight,and may extend at an acute angle radially from a Z-axis longitudinalcenterline toward the bearing surface 615. The projectile may include agenerally ovoid hollow portion 620 that may operate to enhance expansionof the projectile 600 on impact. The blind holes may extend proximate tothe bearing surface 615, and may form a cone shape 635 within theprojectile 600. While the blind holes 605 are illustrated as extendingat a particular angle from the Z-axis longitudinal centerline, it shouldbe understood that the blind holes 605 may extend at any angle suitablefor extending from the meplat 610 to the bearing surface 615 of theprojectile 600. Furthermore, it should be understood that the blindholes 605 may also extend from the meplat 610 to any one of an ogivebase 625 or a shank 630 of the projectile 500.

The through holes or passages extending from a meplat of the projectileto an ogive base, shank, or bearing surface of the projectile, oralternately, extending from an ogive nose of the projectile to an ogivebase, a shank, or a bearing surface of the projectile, may operate toaccelerate rotation of the projectile during flight and may also operateto cause an expansion of the projectile upon impact that causes sectionsof the projectile to spread apart and separate from the projectile uponimpact.

The blind holes or passages extending from a meplat of the projectile toan ogive base, shank, or bearing surface of the projectile withoutextending or penetrating through the ogive base, shank, or bearingsurface may operate to cause an expansion of the projectile upon impactthat causes sections of the projectile to spread apart and separate fromthe projectile upon impact.

It should be understood that there may be a relationship among two ormore of the angle of the holes, the placement of the holes, the shape ofthe projectile, the rotational speed of the projectile, the forwardvelocity of the projectile, and the size of the separated sections ofthe projectile.

Once fired, the aerodynamics of a projectile are affected by theprojectile's rotation which acts to stabilize the projectile duringflight. Rotational forces may operate to cancel effects of any asymmetryof the projectile, minimize ballistic drop, and thus increase the timeof flight. The ballistic coefficient of projectiles incorporating thedisclosed embodiments may also be enhanced due to the acceleratedrotation of the projectile. The increased rotational spin results inreduced projectile yaw, further resulting in less drag, increasedvelocity, less travel time to target, and less time to kill. Usingkinetic energy as the traditional way to rate a projectile'sperformance, doubling the velocity results in quadrupling the kineticenergy. For example, a velocity increase of approximately 10% willquadruple the performance differential of the projectile.

A firearm's damage falloff range is the range at which the firearmimparts 100% of its base damage and the firearm's falloff curve providesthe amount of damage as it decreases with increasing range to thetarget. Use of the projectiles as disclosed may generally result inincreased damage falloff range and increase the range at which thefirearm's falloff curve occurs.

Terminal ballistics and stopping power are aspects of firearm projectiledesign that affect what happens when the projectile impacts an object.The outcome of the impact is determined by the composition and densityof the target material, the angle of incidence, and the velocity andphysical characteristics of the projectile itself. As described above,some embodiments of the disclosed projectiles are generally designed topenetrate, deform, or break apart. For a given material and projectile,the strike velocity is generally the primary factor that determineswhich outcome is achieved. On impact, the meplat, ogive nose and ogivebase sections of the projectiles of some of the embodiments, forexample, illustrated in FIGS. 4A-4D, FIGS. 5A-5G, and FIG. 6, maycollapse at a higher rate than a conventional projectile because of theposition of the holes, cone shapes and hollow cavities of the disclosedembodiments. The collapsed sections of the projectile may be dividedinto sections upon impact, that spread apart and separate from theprojectile, for example, the bearing surface and the boat tail, causinga loss of mass and momentum of the projectile, slowing the forwardmovement of the projectile and making it more likely that the projectileand separated sections remain within the target, thus reducing danger toadjacent objects.

The through holes of the disclosed embodiments may be implemented in anysuitable projectile, including those already manufactured or currentlybeing produced. This allows current or future ammunition producers toincorporate the advantages of the features of the disclosed embodimentsinto existing inventory or future products. Purchasers of ammunitionincorporating the disclosed features may realize improved performancewithout modifying existing firearms.

The holes or passages for both applications may be fabricated usingelectrical discharge machining (EDM) techniques by guiding one or morewire electrodes through the firearm projectile.

The disclosed embodiments are further directed to a method offabricating the projectile with the through holes or blind holes usingEDM. The EDM process is generally based on erosion of a metal workpieceby electrical discharges through a space between a charged workpiece anda charged electrode. The electrode may be made of one or more of brass,copper, graphite, or tungsten.

A high voltage causes a spark to pass through the space which causesvaporization of some of the workpiece material as well as some of thematerial of the electrode. The process can be repeated at a very highrate (200-500,000 cycles per second) while the electrode is guidedthrough the workpiece with the metal removal rate being controlled bythe current density or average current in circuitry controlling thedischarge. The EDM process has the advantage of being able to producevery precise, small diameter passages that may be extremely difficultwith conventional drills. In addition, the EDM process is capable ofproducing passages at various angles to the surface of the workpiece,which may be impossible with conventional drills. As an example, a5-Axes CNC EDM machine may be used to either modify an existingprojectile design or create a new projectile design using EDM techniquesby guiding one or more wire electrodes through the projectile.

FIG. 7 illustrates through holes being machined in an exemplaryprojectile using an EDM machine, and FIGS. 8A-8C show examples ofprojectiles with through holes according to the disclosed embodiments,fabricated using the EDM process. The fabricated projectiles are shownwith electrodes in the through holes illustrating the orientation of thethrough holes after fabrication.

FIG. 9 illustrates blind holes being machined in an exemplary projectileusing an EDM machine, FIG. 10 shows an example of a projectile withblind holes according to the disclosed embodiments, fabricated using theEDM process. The fabricated projectiles are shown with electrodes in theblind holes illustrating the orientation of the blind holes afterfabrication.

While FIGS. 7 and 9 illustrate EDM processes being applied to a singleprojectile, it should be understood that multiple projectiles may beoperated upon at the same time. For example, in applications where asingle electrode may be guided through a single projectile at a time,multiple projectiles may be assembled in a row or matrix, for example, a1×10 matrix, and a corresponding arrangement of electrodes may beassembled in a cartridge or palette attached to an EDM head. An EDMslider may advance the cartridge toward the projectiles while highvoltage pulses are applied to the electrodes, such that the number ofprojectiles assembled together may be operated upon simultaneously,resulting in a significant reduction in production time. In someexamples, a reduction of 30% production time per hole may be achieved.

It is noted that the embodiments described herein can be usedindividually or in any combination thereof. It should be understood thatthe foregoing description is only illustrative of the embodiments.Various alternatives and modifications can be devised by those skilledin the art without departing from the embodiments. Accordingly, thepresent embodiments are intended to embrace all such alternatives,modifications and variances that fall within the scope of the appendedclaims.

Various modifications and adaptations may become apparent to thoseskilled in the relevant arts in view of the foregoing description, whenread in conjunction with the accompanying drawings. However, all suchand similar modifications of the teachings of the disclosed embodimentswill still fall within the scope of the disclosed embodiments.

Various features of the different embodiments described herein areinterchangeable, one with the other. The various described features, aswell as any known equivalents can be mixed and matched to constructadditional embodiments and techniques in accordance with the principlesof this disclosure.

Furthermore, some of the features of the exemplary embodiments could beused to advantage without the corresponding use of other features. Assuch, the foregoing description should be considered as merelyillustrative of the principles of the disclosed embodiments and not inlimitation thereof.

1. A firearm projectile comprising: a plurality of holes spacedequidistant from each other, wherein each hole extends from an upperpart to a lower part of the firearm projectile, and wherein each holeextends at an acute angle from a z-axis longitudinal centerline of thefirearm projectile, causing an accelerated rotation and increasedkinetic energy of the firearm projectile upon firing and an expansion ofthe firearm projectile upon impact that causes sections of the firearmprojectile to separate.
 2. The firearm projectile of claim 1, whereinthe plurality of holes are cylindrical.
 3. The firearm projectile ofclaim 1, wherein the plurality of holes are through holes.
 4. Thefirearm projectile of claim 1, wherein the plurality of holes are openat the upper part of the firearm projectile and blind at the lower partof the firearm projectile.
 5. The firearm projectile of claim 1, whereineach hole extends from an ogive nose to an ogive base of the firearmprojectile.
 6. The firearm projectile of claim 1, wherein each holeextends from an ogive nose to a bearing surface of the firearmprojectile.
 7. The firearm projectile of claim 1, wherein each holeextends from an ogive nose to a shank of the firearm projectile.
 8. Thefirearm projectile of claim 1, wherein each hole extends from a meplatto a shank of the firearm projectile.
 9. The firearm projectile of claim1, wherein each hole extends from a meplat to an ogive base of thefirearm projectile.
 10. The firearm projectile of claim 1, wherein eachhole extends from a meplat to a bearing surface of the firearmprojectile.
 11. The firearm projectile of claim 1, wherein each holeextends at an acute angle from a z-axis longitudinal centerline of thefirearm projectile in both x and y axes directions.
 12. The firearmprojectile of claim 1, wherein each hole extends radially from a z-axislongitudinal centerline of the firearm projectile.
 13. The firearmprojectile of claim 1 comprising a pre-existing bullet through which theplurality of holes are machined.
 14. A method of manufacturing thefirearm projectile of claim 1, comprising: placing an electrodeproximate the upper part of the firearm projectile; directing a streamof dielectric fluid toward a space between the electrode and the upperpart of the firearm projectile; periodically applying an electricalpotential between the electrode and the firearm projectile causing acyclical arcing between the electrode and the upper part of the firearmprojectile, causing an erosion of a portion of the upper part of thefirearm projectile while guiding the electrode through the firearmprojectile, resulting in individual ones of the plurality of holes. 15.The method of claim 14, wherein the electrode comprises one or more ofbrass, copper, graphite, or tungsten.
 16. The method of claim 14,wherein the dielectric fluid comprises deionized water.
 17. The methodof claim 14, wherein periodically applying an electrical potentialbetween the electrode and the firearm projectile comprises applying theelectrical potential at between 50-250 volts DC or AC and between 200 to5000,000 cycles per second.